Method, computer program when run on a computer, computer readable medium and control unit for controlling a multi-clutch transmission

Abstract

A method for controlling a multi-clutch transmission of a vehicle includes activating the central synchronizer to the first active state, such that the speed of a first member of a tooth clutch, attempting to engage the tooth clutch to be engaged, and if the tooth clutch to be engaged is determined not to be fully engaged a predetermined period of time after an initiation of an engagement, the following steps are performed: activating the central synchronizer to the second active state such that the speeds of the two members of the tooth clutch to be engaged are slightly unsynchronized, and engaging the tooth clutch to be engaged.

The invention claimed is: 
     
       1. A method for controlling a multi-clutch transmission of a vehicle, the multi-clutch transmission comprising:
 a first input shaft, a second input shaft, a first shaft, and a second shaft, 
 at least a first and second tooth clutch arranged upon different shafts among; the first input shaft, the second input shaft, the first shaft and the second shaft, wherein each of the first and second tooth clutch is provided with a first and a second member respectively, wherein the first and the second member are in drive connection with one of the first and second input shaft respectively, 
 a central synchronizer provided with a first active state and a second active state for increasing or decreasing a speed of the one of the first and second input shaft which is not transferring torque, depending of which of first and second active statea the central synchronizer is provided in, 
 wherein the first and second tooth clutches can be arranged in an engaged and a disengaged position, whereby in the engaged position the first and second tooth clutch enables an operative connection between the first and second member of the tooth clutch and in the disengaged position the operative connection is disabled, 
 wherein during a gear shifting procedure from a momentary gear to a predicted gear; the method comprises the steps of: 
 activating the central synchronizer to the first active state, such that the speed of a first member of a tooth clutch to be engaged is synchronized with a speed of a second member of a tooth clutch, 
 attempting to engage the tooth clutch to be engaged, 
 if the tooth clutch to be engaged is determined not to be fully engaged a predetermined period of time after an initiation of an engagement, the following steps are performed: 
 activating the central synchronizer to the second active state such that the speeds of the two members of the tooth clutch to be engaged are slightly unsynchronized, and 
 engaging the tooth clutch, to be engaged. 
 
     
     
       2. The method according to  claim 1 , wherein the method is used during a gear shifting procedure of pre-selected gear. 
     
     
       3. The method according to  claim 2 , wherein the predicted gear is a third gear, the tooth clutch is a first tooth clutch provided with one member upon the first shaft and is connecting a gearwheel with the first shaft. 
     
     
       4. The method according to  claim 2 , wherein the predicted gear is a sixth gear, the tooth clutch to be engaged is a second tooth clutch connecting a gearwheel arranged upon the second shaft and in its engaged position connecting two gearwheels rotatably arranged upon the second shaft. 
     
     
       5. The method according to  claim 1 , wherein the method is used during a change of an active gear. 
     
     
       6. The method according to  claim 1 , wherein the first shaft is a main shaft and the second shaft is a countershaft. 
     
     
       7. A computer comprising a computer program for performing the steps of  claim 1  when the program is run on the computer. 
     
     
       8. A non-transitory computer readable medium carrying a computer program comprising program code means for performing the steps of  claim 1  when the program product is run on a computer. 
     
     
       9. A control unit for controlling a utility vehicle, the control unit being configured to perform the steps of the method according to  claim 1 .